1. Go to https://en.wikipedia.org/
2. Make sure you are logged in.
3. Click on "Preferences" in the top right.
4. Click on the "Beta features" tab, the second from the right.
5. Enable "New filters for edit review"
6. Click "Save" at the bottom of the page.
7. Go to your Watchlist by clicking it on the top right, near "Preferences", or by going to https://en.wikipedia.org/wiki/Special:Watchlist
8. Change the Active filters so there are only "Page edits", "Page creations", and "Logged actions" left.
9. Click the bookmark icon on the right side to save the Active filters.
10. Reload the page, and then select the name you gave those Saved filters from the drop-down menu on the right side.
11. The blue markers to the left of each diff entry in my Watchlist (which are solid if the change has not yet been viewed and empty if it has) aren't appearing. When the page is loading, they do appear, but only for about half a second, and then once the page has fully loaded, they disappear.